Patent GB-972805-A (GB)
Title: Manufacture of pigment compositions
Inventor: BARRON GORDON
IPC: C09B48/00
Filed: 1962-03-14
Abstract: The invention comprises a pigment composition containing a pigment, which may be inorganic, intimately incorporated with a minor quantity of an organic pigment derivative which has a secondary or tertiary amino group attached through a methylene group.  The organic pigment derivative may be coated on to the particles of the pigment. Inorganic pigments specified are lead chromate, titanium dioxide, carbon black, iron oxide and Prussian blue.  The organic pigment derivatives may contain a secondary or tertiary amino-methyl group attached to copper phthalocyanine, linear quinacridone, isodibenzanthrone or 4: 41-bis-(6 - methylbenzthiazyl) - azobenzene. The organic pigment derivative is incorporated with the pigment (a) by milling them together in solid form, (b) by dissolving them together in sulphuric acid and coprecipitating them with water, (c) by mixing them if desired while raising the pH in the presence of a dilute acid or organic liquid, which may be the medium in which the pigment composition is to be employed, in which the organic pigment derivative is soluble, a pigment whose particles are coated with the organic pigment derivative being obtained, or (d) by milling them if desired while raising the pH in the presence of a dilute acid or organic liquid in which the organic pigment derivative is insoluble. In an example (18) a lead chromate pigment is stirred in methanol with an aqueous lactic acid solution of a mixture of bis- and tris-(isopropylaminomethyl)-4: 41 -bis - (6 - methylbenzthiazyl)azobenzene while raising the pH.  Specification 949,739 is referred to.ALSO:Alkyd paints are pigmented with a pigment composition containing an inorganic or organic pigment intimately incorporated with a minor quantity of an organic pigment derivative which has a secondary or tertiary amino group attached through a methylene group.  The organic pigment derivative may be coated on to the pigment particles or merely mixed therewith.  In examples, alkyd resin paints which may also contain titanium dioxide are described containing the following pigment compositions: (7-9), copper chlorophthalocyanine and copper bis- and tris-(isopropylaminomethyl)-phthalocyanine; (10), copper chlorophthalocyanine and copper bis-and tris-(dicetylaminomethyl)-, (N-cetyl-N-b -hydroxypropylaminomethyl)-, (N-dodecyl-N-b -hydroxyethylaminomethyl)-, (N-methyl -N- benzylaminomethyl)-or (cetylaminomethyl)-phthalocyanine or copper pentakis-(diethylaminomethyl)-phthalocyanine; (13), copper phthalocyanine and copper tris-(cyclohexylaminomethyl) (18) lead chromate and a mixture of bis- and tris-(isopropylaminomethyl) -4:41-bis- (6-methylbenzthiazyl) azobenzene; (19), the disazo dye obtained by coupling tetrazotised 3:31-dichlorobenzidine with o-acetoacetic - anisidide and a mixture of bis- and tris-(isopropylaminomethyl)-4:41-bis-(6-methylbenzthiazyl) - azobenzene; and (21) linear quinacridone and isopropylaminomethylquinacridone. Specification 949,739 is referred to.ALSO:The invention comprises a pigment composition containing an inorganic or organic pigment intimately incorporated with a minor quantity of an organic pigment derivative which has a secondary or tertiary amino group attached through a methylene group. Inorganic and organic pigments specified are lead chromate, titanium dioxide, carbon black, iron oxide, Prussian blue, copper phthalocyanine, copper chlorophthalocyanine, flavanthrone, linear quinacridone and pigments of the mono- and disazo series. Organic pigment derivatives, made by reacting a chlormethylated pigment with a primary or secondary amine, may be derived from copper phthalocyanine, linear quinacridone, isodibenzanthrone and 4: 41 - bis - (6 - methylbenzthiazyl) azobenzene.  The organic pigment derivative is incorporated with the pigment (a) by milling them together in solid form, (b) by dissolving them together in sulphuric acid and co-precipitating them with water, (c) by mixing them if desired while raising the pH in the presence of a dilute acid or an organic liquid, which may be the medium in which the pigment composition is to be employed, in which the organic pigment derivative is soluble, a pigment whose particles are coated with the organic pigment derivative being obtained, or (d) by milling them, if desired while raising the pH, in the presence of a dilute acid or organic liquid in which the organic pigment derivative is insoluble.  In Examples: (12) Monolite Yellow GL and (20) flavanthrone coated with a mixture of bis- and tris-(isopropylaminomethyl)-4:41-bis-(6-methylbenzthiazyl) - azobenzene are milled into lithographic varnishes to give printing inks.  Specification 949,739 is referred to.